The
last of five space walks finally fixes the problems with the Hubble telescope.

The
Hubble telescope had a design flaw - the main mirror was said to be flatter than
it should have been. It was only out by 1/50th of the width of a human hair, but
the result was it was only as good as an earth based telescope which was a major
embarrassment for NASA who had spent $1.55bn on the project.

The
main flaw was rectified, apparently, by placing on it a sort of contact lens which
corrected the defect. The astronauts also fixed around 10 other defects.

Due
to the rotation of the planet, the astronauts (Story Musgrave and Jeff Hofman)
traveled at 17,000 miles an hour while correcting the telescope. They were 360
miles above the Earth's surface.